Approaches have been made in recent years to connect portable terminal devices (for example, mobile phones) that are brought into vehicles and on-vehicle devices by Bluetooth® to allow cooperative operations between the applications of the portable terminal devices and the on-vehicle devices. For example, an on-vehicle application is executed using a portable terminal device to display data on the display of an on-vehicle device, operations are caused by inputting data using an on-vehicle device, such as a steering switch, and, in some work using vehicles, destination information that is transferred from an office PC to a portable terminal device is shared with an on-vehicle device in a vehicle (see, Japanese Laid-open Patent Publication No. 2006-184108).
With the above technologies, a portable terminal device, on which a necessary application is started, is brought into a vehicle in a connection-wait state, and an on-vehicle device issues a connection request to the portable terminal device that is found by device searching and, accordingly, the on-vehicle device connects to the application on the portable terminal device, which allows cooperative operations between the on-vehicle device and the portable terminal device.
In conventional technologies, if only one portable terminal device is brought into a vehicle, the on-vehicle device connects to the portable terminal device. However, if there are some portable terminal devices in a vehicle (for example, if there is a person in a passenger seat who also has a portable terminal device), the on-vehicle device may not determine by itself to which portable device the on-vehicle device may connect.
A method can be employed in which an on-vehicle device searches portable terminal devices in response to starting the vehicle engine, temporarily connects to all of the found portable terminal devices, and then sends a message to confirm whether to perform cooperative operations with the on-vehicle device to each of the portable terminal devices. A message is then displayed on the screen of each of the terminal devices to prompt users to choose whether to connect to the on-vehicle device. However, this method is not preferable because the users have to perform time-consuming operations.
In other words, it is a significant objective, even if there are a plurality of portable terminal devices that are communicable with an on-vehicle device, to connect the on-vehicle device to a portable device to which the on-vehicle device should connect without requiring the users to perform time-consuming operations.